Take a pressure cooker and add 1 tsp of oil and spatter cumin seeds, green chilli, cardamom and then saute onions with the ginger garlic paste for 2-3 mins till the raw smell goes away.
Now add overnight soaked green chana, horse gram and chick peas along with chopped beetroot and mix well.
At this point add raw mango, cumin powder, salt and then with some 1 cup of water pressure cook it for 2-3 whistles.Open the cooker after the pressure is released and dry up all the water.
Now cool it down and transfer in a mixer grinder and add chat masala , lemon juice, mint leaves and make a paste of it. Initially it will take time as the paste will be quite thick , you can use a spatula to mix it evenly as you do it in couple of times.
Next transfer it in a bowl and keep it in refrigerator for some 20 mins and then take it out and make small patties. Remember since we are not using any bread or binding medium, the cooling will make it dry enough to handle gently.
On a hot pan smear some oil and cook the kababs from both sides and serve with fresh pudina or coriander chutney.